With the development of semiconductor IC manufacturing technology, the wafer size increases from 150 mm, 200 mm to 300 mm or even bigger, the manufacturing cost of FAB is becoming more and more expensive. How to effectively exploit the limited production space of the FAB, improve the productivity of production equipment, shorten production cycle and the like are becoming more and more important.
Please referring to FIG. 1 and FIG. 2, FIG. 1 is a front view of a conventional equipment platform system, FIG. 2 is a top view of the conventional equipment platform system. The conventional equipment platform system of the FAB includes: a hexagonal working platform 102, a front-loading wafer device 101, which is located at the front of two sides of the hexagonal working platform 102; a process chamber 103, which is mounted at the other four sides of the hexagonal working platform 102; a built-in vacuum robot (not drawn), which is located in the hexagonal working platform 102, is used for carrying the wafers to each process chamber 103; the hexagonal working platform 102 has a wafer loading chamber 106, the front-loading wafer device 101 includes a cassette or FOUP (Front Opening Unified Pod) loading unit 105 and a robot (not drawn), is used for taking out the wafers from the cassette or FOUP loading unit 105, and placing the wafers in the wafer loading chamber 106; in addition, among equipment platform systems, an overhead transfer device 104 is used for carrying the cassette or FOUP.
Please referring to FIG. 3, FIG. 3 is the flow schematic of a conventional wafer transfer method. The conventional equipment platform system's transfer procedure of the wafer includes:
Step 21: the overhead transfer device 104 places the cassette or FOUP to the cassette or FOUP loading unit 105 of the front-loading wafer device 101;
Step 22: the robot of the front-loading wafer device 101 takes out the wafer from the cassette or FOUP and places it in the wafer loading chamber 106;
Step 23: the built-in vacuum robot of the hexagonal working platform 102 takes out the wafer from the wafer loading chamber 106, and place it in the process chamber 103.
In the condition of placement state of the front-loading wafer device, there are at least two wafer loading chamber 106 mounted at the sides of the hexagonal working platform 102 in general. However, the wafer loading chambers 106 occupy at least two mounting positions of the process chamber 103, so that the hexagonal working platform 102 can only mounts one to four process chamber 103, the space is not fully used, and the efficiency of the wafer transfer decreases.